COS 60-1
Common sympatric canine species as sentinels of disease in the Mexican wolf (Canis lupus baileyi) reintroduction landscape
Several threatened canine species have experienced population reductions due to infectious disease where abundant sympatric canines act as reservoirs. Disease surveillance of the latter presents a potential conservation tool. In this study, we explore a surveillance protocol for gastrointestinal parasites, assessing its feasibility as a supplement for on-the-ground surveys of reintroduced Mexican wolves (Canis lupus baileyi). Multiple parasites (e.g., Giardia, Echinoccocus) can infect wolves, coyotes, foxes, and dogs that share the reintroduction landscape in the southwestern US. Managed by the Mexican Wolf Recovery Program (MWRP), the population of ~75 Mexican wolves has not yet experienced severe disease outbreaks. However, the existing pathogens carried by more abundant sympatric canines sharing the landscape are the most likely source of pathogens that could infect wolves.
In 2013, wolf fecal samples were obtained during annual MWRP veterinary procedures. Ad-hoc sampling for other canine scat occurred during MWRP field surveys. Our approach represents a novel application of next-generation sequencing using a universal eukaryotic primer for 18S sRNA, which can detect micro-eukaryotes, including parasites, from scat samples found in environmental conditions. We compare the efficacy of this method to floatation parasitological survey methods
Results/Conclusions
We successfully sequenced 21 samples on an Illumina MiSeq with the universal eukaryotic primer for 18S sRNA. Following bioinformatics processing with QIIME, we found evidence of several known parasitic taxa. Protozoans included Sarcocystis (prevalence: 24%), Gregarinasina (prevalence: 14%), and other coccidians (prevalence: 10 %). We detected signal from arachnids, likely ectoparasitic mites, in 10 % of samples. Helminths found included oxyurid nematodes (prevalence: 5%) and tapeworms (prevalence: 5%). Fungal taxa involved in decomposition dominated the eukaryotic microbiota, probably reflecting the environmental conditions in which samples were collected. Fecal floats corroborated the next-generation sequencing findings and sequence data aided visual identification. Currently, parasite pressure in the reintroduction landscape appears variable and low. Overall, given the successful detection of several parasite phyla from samples exposed to environmental conditions, surveillance of gastrointestinal parasites using next-generation sequencing is a promising supplement to current management and monitoring of these threatened canines. Increased sample size and longer term collection will likely yield meaningful patterns and insights about potential disease outbreaks. This ad-hoc, non-invasive sampling strategy for disease surveillance presents a promising approach, bridging wildlife management and novel molecular tools.